1. Field of the Invention
The present invention relates to a technology for processing an image acquired by an imaging apparatus.
2. Description of the Related Art
In recent years, an imaging apparatus called a digital camera, which uses a CCD or any other imaging device to acquire an image of a subject (captured image), has been widely used. Since such an imaging device provided in a digital camera produces electric charge called dark current, a captured image acquired by the imaging device also contains noise due to the dark current (also referred to “dark current noise”).
An example of a method for removing dark current noise from a captured image has been proposed (JP-A-2000-209506). In this technology, after the imaging device is exposed to light (final exposure), imaging operation is carried out with light impinging on the imaging device blocked (dark exposure), and the output from the imaging device in the dark exposure is subtracted from the output from the imaging device in the final exposure to remove dark current noise from a captured image.